1. Field of the Invention
The present invention relates to a computer system, a state acquisition method, and a state acquisition program product, and in particular, to a computer system, a state acquisition method, and a state acquisition program product, having a function of storing a computer state immediately before occurrence of a trouble, for investigating causes of the trouble.
2. Description of the Related Art
In general, in methods for investigating the cause of a trouble in a computer, there are a method in which data necessary for analyzing the trouble, such as contents of a memory at the time of occurrence of the trouble, is stored in a file and the data is analyzed to investigate the cause of the trouble; and a method in which data necessary for reproducing the trouble, such as contents of a memory immediately before occurrence of the trouble, is stored in a file and the trouble is reproduced using the data to investigate the cause. In the former method, though it is relatively frequently used, there is a difficulty in reliability because processing for storing data must be performed in an unstable state after the occurrence of the trouble. Contrastingly, the latter method has no such problem because data is stored before the occurrence of the trouble.
JP-A-10-198578 discloses an example of the latter method. In the method disclosed in JP-A-10-198578, during a time period till some trouble occurs on a program being executed, the processor executing the program acquires and stores data for restart, called check points, at predetermined time intervals. As a result, at the time of occurrence of the trouble, data immediately before the occurrence of the trouble is stored.
As described above, in the conventional method of acquiring data necessary for reproducing the trouble, data is acquired and stored at predetermined time intervals during a time period till the trouble occurs. Therefore, there is a problem that overhead upon execution of the program increases and it brings about delay in normal program processing. In particular, the problem becomes remarkable as the amount of data to be stored increases, for example, when it is a huge amount of data including all images in the main memory, files on an external memory device used by the program, and so on.